Centralized information service



.April 25, 1939. c. DE 'VRIENDT ET AL n CENTRALIZED INFORMATION SERVICE 4 Sheets-Sheet 1 Filed Feb. 12, 19

, m whx INVENTORS C'- E VR/ENDT HEABORZER AT TORNEV April 25 1939. c. DE VRIENDT ET AL 2,155,933

' GENTRALIZVED INFORMATION SERVICE L Filed' Feb. 12, 1937 4 Sheets-Sheet 2 FIG. 2

C. DE VR/ENDT wv vRf H. 5,4. BORZER ATTORNEY April 25, 1939. CpDE VRIENDT ET AL CENTRALIZED INFORMATION SERVICE Filed Feb. -12, 1937 4 Sheets-Sheet 3 DE I/R/ENDT H. E A. BORZE R IN VE N TORS m bbx U N R m T A April 1939- c. DE VRIENDT ET AL 2,155,933

CENTRALIZED INFORMATION SERVICE Filed'Feb. 12, 1937 4 Sheets-Sheet 4 INVENTORS Patented Apr. 25, 1939 UNITED STATES PATENT OFFiC'E logne-Billancourt,

France, assignors to western Electric Company, Incorporated, New York,

N. Y., a corporation of New York Application February 12, 1937, Serial No. 125,41-3 In France April 25-, 1936 13 Claims.

This invention relates to telephone exchange systems and more particularly to facilities for giving information service from a centralized center to subscribers whose lines terminate in different oifices of the system.

In a large city having telephone networks with multiple ofiices and particularly with automatic ofiices, one of the difficulties consists in the organization of the information service. It is clear that in order to give an eflicient and rapid service of this nature which may be of a quality comparable with that of the usual automatic service, the arrangement hitherto generally maintained, of operators allocated to this service in each office constitutes an unfavorable element not only from the point of view of the subscriber, but also from that of the utilization of the stafi by reason of its great dispersion. It is obvious that a good information service would be more easily obtained by concentrating all the stafi allocated to this service in a single point of the network, to which the subscriber's call could arrive in an automatic manner and tobe able then to be rapidly transferred to the service capable of giving the exact information required. Such a centralized information service can be attained by methods borrowed from the art of manual telephony, or again an effort might be made to utilize methods of exploitation as automatic as possible. In the first case the subscribers calls can arrive at the central information service at operators receiving sets equipped with single cords on which the said calls are taken. The information operators positions of the various services would be represented on multiple jacks permitting the receiving operators to direct the 7 calls received to a further operator of the appropriate service. The call thus extended to a particular service would, however, have to be adapted to be transferred to another service if this appeared necessary, and finally, it would also be desirable that any call might be transferred to the supervisory position. Moreover, by reason of the nature and variety of the information that these various operators may be called upon to give to the public, they must have at their disposal varied and usually voluminous documents such as telephone directories or various works of reference whose presence on their desk accords ill with that of the numerous plugs or keys. It is consequently clear that it is highly desirable to develop a system of automatic distribution of the calls for information which while giving the desirable facilities mentioned above would also have the advantage of accommodating itself to automatic exchange and on which arrive the calls L of 'thesubscribers to any information-service;

Fig. 2 shows the input junction circuit to; the information center which represents the termination at this center of the outgoing junction shown i-nFig. 1;

Fig. 3 shows the circuit 'of a receiving operator's position and control to which areconnected the junction circuits according to Fig. 2;

Fig. 4 shows a circuit of an information or supervisory operators position, which is connected to the input junction circuit of Fig. 2

after a transferring operation has been effected by the control operator serving the position circuit shown in Fig; 3; and M Fig. 5 shows the method of association of the circuit drawings of Figs. 1 to 4. J k H On long lines the general operation of the system is as follows:

The subscriber after having dialed the number corresponding to information is connected through the circuits of Figs. ;1 and -2 to a receiv- J ing operators or control position (Fig. 3) When the call arrives the operator perceives a tone "in her receiver at the same time that a call lamp {is lighted. The operator is then automatically connected to the calling subscriber without having to manipulate any key. The line of the call- -ing subscriber, like all the circuits employed by the connection, is maintained under the control of the operators position so as to maintain "the connection with a view to possible transfer or even, if necessary, to permit the origin of misch evous calls to be identified. When, supposing that she has been able to do so, the operator has given the required information and the calling subscriber hangs up, she gets a supervisory signal and actuates a key to release the connection to free her own set.

If, however, the operator wishes to transfer the calling line to another service, she "dials a certain number of one digit which corresponds to 'the 3 energization of the relay established at the secondary selector switch. The

desired service.

The corresponding impulses are received and marked in the input junction circuit by a step-by-step switch and all the junction finders of the circuits (Fig. 4) of the service concerned, hunt for the call thus registered. The control operator, however, remains in connection with the subscriber until the call is effectively taken by a second operator. When the operator perceives a supervisory signal informing her that a call has actually been transferred, she actuates a key in order to release her position. If the receiving operator had had to transfer the call to a supervisory position, she would have dialed a special number reserved for this position. If for any reason, such for example as a case of surcharge, the transfer is not completed, she can cancel this operation by actuating a key.

Moreover, each operator of the various services can at will retransfer a call to other information positions or to a supervisory position. It is also possible to send the call again to a receiving operator and for this purpose all the information positions and the supervisory position are provided with a special key. Finally, an operator can also as desired perform an operation which will determine the metering of the call against the calling subscriber. One of the interesting features of this system of distribution consists in the fact that the retransfer of a call is obtained by means of an impulse device, thus permitting access to .a relatively large number of services and in the fact that a call can be successively transferred as often as necessary and always by means of the same key manipulation, the number dialed only depending upon the service to be obtained and not on the position from which the call is transferred.

When a call is made to the information service, it terminates at the office of origin in the circuit of Fig. l which is connected to the banks of primary or secondary selectors in the well-known manner. The engagement of a circuit in accordance with Fig. 1 takes place in this circuit by the 82 over the talking loop relay S1 in operating cuts off the potential applied through the resistance Rt to the third wire so as to permit the advance of the secondary selector and remains locked to the earth on the third wire. By its inner right-hand work contact it connects a return ringing tone intended for the calling subscriber and by its outer right-hand work contact it connects, through the polarized relay A and the self-inductance SS, an earth over the wire a to the input junction circuit of Fig. 2. In this circuit the relay Sai, connected on the one hand to the wire a and on the other hand to the battery through rest contacts of the relays C and S, is actuated, and by its left-hand work contact closes a circuit for the relay A1, which in turn causes the rotation of the finder MF, whose circuit is closed through the left-hand rest contact of El, the outside right-hand rest contact of Ti, the rest contact Gt, the inside lower work contact of A1, to earth. The hunting for a con- .trol operator takes place under the control of and the resistance Rs.

The potential of availability of the is given by the relay D (Fig. 3)

to battery, which is conthe relay Gt. control operator relay T is energized, that is to say, that the operator is at herposition. As soon as the finder MF meets an idle control operator's circuit, the relay Gt is actuated, cuts off the circuit of the electromagnet MF and closes the circuit for the connection relay Ct. The relay Ct on the one hand closes the wires a and b to the operators position and on the other hand connects an earth to the low resistance winding of Gt, so as to prevent another finder from stopping on the control operators position which has just been engaged. Moreover, by the upper work contact of Ct and a rest contact of C, the relay Sbi is connected to earth and consequently operates in series with the relay B of the circuit of Fig. 1. This relay B operates the relay Rd, which by its left-hand rest contact determines the unlocking of S1 and consequently the momentary retraction of the relay sin, but the relay A1 is held by the work contact of SDI. By its right-hand work contact Rd connects to the incoming wire I), the relay Sb, which operates in series with the relay of the wire b of the connecting circuit, thus preventing the subscriber from being able to release the connection by hanging up. Moreover, the relay Sa through the work contact of Sb is connected to the incoming wire a and operates in series with the self-inductance connected to earth at the connection circuit. Sa supplies on the one hand a holding earth to the relay Rd and on the other hand connects earth to the conducting wire a which, replacing that given by S1, again determines the operation of Sen (Fig. 2).

At the moment when the low resistance winding of the relay Gt is introduced in the test circuit, the relay D of the control operators posi-' tion is actuated. This relay connects an earth to the relay G which then operates and connects the secondary of a tone transformer to the receiver of the operators position; at the same time, the relay G causes the actuation of the relay Ja, which in turn causes the actuation of Jb, which remains locked to the earth given by D. Relay J b in actuating short-circuits J a, which falls back and at this moment G also falls back short-circuited. During the period that G has been in operation, the operator will have heard the warning tone of the arrival of a call. Finally, the relay J 1) lights the lamp CL. The relay N is .actuated in the battery feed loop through the relay S of the circuit of Fig. 2, but the resistance of the two windings of N in series is such that relay S does not operate under these conditions. The relay N lights the lamp SL, which will give the subscribers supervision.

Two cases may arise: either the control operator can give the information required by the subscriber, or else she has to transfer the call to one of the information or supervisory positions.

In the first case, when after having received the information the calling subscriber hangs up, the operator obtains the supervision of this operation in the following manner:

The hanging up of the subscriber causes the successive retraction of the relays Sa and S114 in the circuits of Figs. 1 and 2, the latter of which opens the earth of the left-hand winding of the relay S (Fig. 2) and determines the retraction of the relay N in the controlling operators position circuit (Fig. 3). If the operator has to cause the metering for the information given, she temporarily presses the key CC, which has the effect of actuating the relay S (Fig. 3), which connects a positive battery on the wire a of the junction, which causes the operation of the polarized relay A in the circuit of the ofilce of origin (Fig. 1). The relay A gives an earth in order to hold the relay Sc, and opens the incoming wire I) which determines the retraction of Sb and also of a relay in the wire bin the connection circuit which and introducing its low will advance into such a position that the metering will take place at the time of the release. If the operator does not wish to meter, it is sulficieht for her in order to release the subscriber, while freeing her position, to press the key RC. in efiect key RC throughthe wire "c connects an earth to the bankc of the step by step switch SM of the circuit of Fig. 2 and by means of normal position terminal of this bank the relay 0 is actuated and locked. Relay C connects the relays Sin and Sbi in series across the wires a and b, so that relay Sbi having earth removed, releases and consequently also the relay A1, and successively all the other relays operated in the two circuits.

Let now suppose that the operator cannot give the information to the subscriber and is obliged totransfer him to an information position. In this case the operator by means of the dial on her set will dial the number of the information position which is likely to fulfill the subscribefs requirement. As soon as she begins to dial, earth is connected through the off-normal contact of the "dial to the armature 'of the relay L. This relay being operated at this moment nothing happens, but as soon as thedial returns, the relay L operates at the rhythm of the impulse ccnta'ct of the dial and during each opening sends an earth over the terminal and the brush e of the finderMF (Fig. 2) and by means of 'a'work contact of relay 'Ct to the step-by-step switch SM. The latter advances by a number of steps corresponding to the digit sent and the relay I, which is in series with the electromagnet of the step-by-step switch, operates in response to the first impulse and remains operated until the end of the series. As soon as relay I has reclosed its normal contact, it "connects a battery to the left-hand winding of the relay T), which is actuated and locked by its right-hand winding to the earth of a work contact of relay A1. It will be noted that the circuit of the relay Gthas Been paralleled by a circuit passing through a work contact of relay Ct and a rest contact of J, so that when T) opens its rest contact the relay Gt is maintained and the control operator remains in communication with the calling subsci'ib'er. As soon as the relay T is operated, the battery at the rest contact of relay I is transferred to one terminal 'of the winding of the relay J and "of a resistance in paralleL th'e other terminal of this relay being connected through brush and a terminal of the bank b 'of switch "SM, towards the multiple 'bank terminals d of all the finders IF1 and IFz of the groups of circuits according'to Fig. 4, corresponding to 'a given information service, and inoreo've'r, through a single resistance Rd, to thestarting relay St corresponding to this group. This relay operates and in turn operates the relay Cs, whichc-loses the circuits of the finders IFl and IF2. When one of these finders, for example IFi reaches the terminal d, which is under potential, the relay Hci operates, stopping the rotation of the finder resistance winding in series with the low resistance winding of relay Sci, which also operates. St is then shunted and falls back and consequently also relay Cs and the other finders IF are stopped. V

Moreover, relay Sci operates relay T1, which connects the wires a, b, c, e of the circuit of Fig. 4 to the corresponding connections of the junction circuit Fig. 3. Relay T1 operates r'ela'y P, which connects the bperators s'etto a tone induction coil. Relay Pin turn operates relay Q, which a vt ork contact 3 is locked mtheeartn at relay "r, and relay Q itself operates relay M, which the kefy' Rela'yQ also lights the ringing lamp SL and short-circuits relay P,which falls back in era-er to discontinue the application of tone to the operators set and to put her in connection with the wires (1 and b in order to connect her with the subscriber. Through four rest contacts the relay M epens the *circl its of the finders IE1 and IR; as well as those of the high resistance windings or the test relays Her and H02, thus preventing the b'per ors circuit from being able to get 'anc'ther call. Finally, the reIaIv N in loop of thewir'es it "and 19 operates in series with the two windings or the relay S of the circuit of Fig. 2, and maintains the operated relay "I'i locked. v

Moreover, the control operator has the super'- vision of the transfer in the following manner: r As sodn as the switch SM following the dialing impulses has left its normal position, the relay K of thecontrol operator's position is actuated the rest contact or th'eke'y TO, the wire and brush c 'of the 'find'er MP, the bank c or to battery through the winding or the magnet SM its interrupter contacts. relay K lights the superv sory transfer i'ainp TL. If for any reason the "trahsferdo'es not take place, lamp remains lighted and the control operator can cancel t e eparation by pressing key TC. d this she connects fa 'directe'ar'th to the winding of magnet SM through its interrupter contacts and "consequently the step by-step switch renirns to normal. The control operator ph eckthe to normal n'nser TF1, tor example, 4 place. epei-atien or the circuit of Fig, 4 takes place as has already been described above. tiin'efof the introduction of the low resistance \ifin'd'ih'g foijthe relay H01, the relay J "of the circuit er Fig. 2 been operated. Relay J causes at its rest contac't the opening of "the cirthe earth er the bank a or the step by step switch SM. A third contact of relay J causes the operation er the relay C, which in turn is locked of relay A1. The opera- 1 already een seen above,

ra ier contacts "and thus causes the return of this step-by-s'tep switch to normal. As soon as the relay Ct falls back, the lamp TL of the control eperater's position is extinguished indicating to the latt'er that the transfer has taken place.

'rth'er, as seen as the circuit or the "relay Gt has 'be'eh cllt "Off by the operation of relay J, the relay F 6f the control position, no longer being shunted, is 'actua'tedflholding this position locked and inaccessible owing to the introduction of the seams l'oti resistance Winding of relay F. The 'c'ontrol bp'erator "can thl'l's Write certain mfbllfia is locked to the earth of the key RC, which releases renders the circuit supervisory position,

tion without being disturbed by a fresh call. The locked condition of the control position is indicated by the fact that the lamp CL is burning. As soon as she wishes to release her position, the operator presses the key RC and all the locked relays are released.

For the information operator two cases may arise, as for the control operator, according to whether she can or cannot give the information desired by the subscriber.

In the first case, when the subscriber has received the information and hung up, he causes the release of all the apparatus of the junction circuit of Fig. 2, which causes the retraction of the relay N in the circuit of the information position Fig. 4. Relay N unlocks relay T1, which falls back, opens the wires a, b, c, e and releases the relay Q, which puts out the lamp SL. The extinction of this lamp indicates to the operator that the subscriber has hung up. The relay M remains locked, however, to the earth given by the key RC, thus the lamp CL remains alight and the relay M prevents the circuit of this operator from taking a fresh call. The operator thus remains cut off, which permits her to take notes if necessary without being disturbed. As soon as she wants to release her position, she presses the relay M and available for a new call.

Let us now suppose that she cannot give the information to the subscriber. Under these conditions she can, like a control operator, transfer the call to another information position or to a or even to a control position if this should be necessary. For the latter operation it is suflicient for her to press the key Age.

gsumes its normal condition.

'the information operator vise the transfer by means of a lamp and to cancel it if it For the normal transfer she manipulates her dial which, as for the control position, sends impulses through the impulse relay L towards the step-by-step switch SM of the circuit according to Fig. 2. The transfer to any position then "takes place under conditions similar to the transfer from the control position with the difference that when the transfer is effected, the connection to the information operators position re- 5 mains maintained by relay N being operated. The

operator can thus assure herself of the completion of the transfer, after which she releases her position by pressing the release key RC. If a subscriber does not hang up after receiving the the information operator if the key BC is equipped,

desired information,

When this subscriber hangs up, fall back as well as the the junction circuit re- If it be desired that shall be able to superrelays A1 and B1, and

should. not be completed, it is suflicient to provide in the circuit of Fig. 4 the relay K and 'control positions positions have a I the lamp TL as well as the key TC, then the key BC must be omitted and the possibility of blocking the subscriber by means of the relay Bl is only left to the supervisory positions. Like the the information or supervisory key such as CC to control the metering if necessary. The method of operation of this key is exactly the same as that already described for the control operator's position.

It is obvious that, when employing the finders ,lF with six brushes instead of five, it is possible 2,75.

to maintain for the information operators the It is also clear that with the same number of wires in junction circuits and operators circuits, that is, five in the example chosen, the transmission of impulses in order to indicate the service may be obtained by actuating one of the keys, of a key pulsing keyboard by using in the junction circuit polarized and marginal relays and a set of marker relays, and in the operators circuit positive and negative battery impulses.

It is finally clear that the system is not limited C to a capacity of access of ten services at a maximum, and could easily be adapted to a larger number, for example, by using a step-by-step switch of greater capacity, directed by means of two sets of successive impulses, or in any other,

well-known manner.

The embodiment described above has been elaborated in order to operate specifically in a particular network, but it is obvious that by a few adaptations in of realization which it embodies would immediately be applicable to any other automatic network with multiple ofiices and might also be further adapted to a network containing manual ofiices.

What is claimed is:

1. In a telephone system, a plurality of operators positions, impulse generating means at each of said positions, means for extending a connection to one of said positions and means for transferring said connection to another one of saidoperators positions by means of a single operation of the impulse generating means at said first position.

2. In a telephone system, a plurality of operators positions, impulse generating means at each of said positions, means for extending a connection to one of said positions and means for transferring said connection from one of said positions to another by means of a single operation of the impulse generating means at the transferring position.

3. In a telephone system, a plurality of operators positions, impulse generating means at each of said positions, means for extending a connection to one of said positions and means for repeatedly transferring said connection from position to position by means of single operations of the impulse generating means at the transferring position.

4. In a telephone system, a plurality of operators positions, impulse generating means at each of said positions, means for extending a connection to one of said positions, means for transferring said connection to another one of said operators positions by means of a single operation of the impulse generating means at said first position, and means to indicate to said first position that the transfer has been completed.

5. In a telephone system, a plurality of operators positions, a dial at each of said positions, means for extending a connection to one of said positions and means for transferring said connection to another one of said operators posisome of the circuits, the means ,30

tions by means of a at said first position.

6. In a telephone system, a plurality of operators positions, a dial at each of said positions, means for extending a connection to one of said positions and means for transferring said connection from one of said positions to another by means of a single operation of the dial at the transferring position.

7. In a telephone system, a plurality of operators positions, a dial at each of said positions, mean for extending a connection to one of said positions and means for repeatedly transferring said connection from position to position by means of single operations of the dial at the transferring position.

8. In a telephone system, a plurality of operators positions, a dial at each of said positions, means for extending a connection to one of said positions, means for transferring said connection to another one of said operators positions by means of a single operation of the dial at said first position, and means to indicate to said first position that the transfer has been completed.

9. In a telephone system, an incoming trunk circuit, a plurality of control operators positions each having a dial, means for connecting said trunk circuit with an idle one of said positions, a plurality of other operators positions having access to said trunk circuit, and a marker switch in said trunk circuit controllable from the dial of a connected control operators position, for directing the connection of one of said other operators positions to said trunk circuit.

10. In a telephone system, an incoming trunk circuit, a plurality of control operators positions single operation of the dial plurality of other operators positions having access to said trunk circuit, a marker switch in said trunk circuit controllable from the dial of a connected control operators position for directing the connection of one of said other operators positions to said trunk circuit, and a dial at each of said other positions for controlling said marker switch to direct the transfer of the connection of said trunk circuit from one of said other positions to another of said other positions.

11. In a telephone system, an incoming trunk circuit, a plurality of control operators positions each having a dial, means for connecting said trunk circuit with an idle one of said positions, a plurality of other operators positions having access to said trunk circuit, a marker switch in said trunk circuit controllable from the dial of a connected control operators position for directing the connection of one of said other operators positions to said trunk circuit, and means thereupon operative for disconnecting said trunk circuit from said control operators position.

12. In a telephone system, an incoming trunk circuit, a plurality of control operators positions each having a dial, means for connecting said trunk Circuit with an idle one of said positions, a plurality of other operators positions having access to said trunk circuit, a marker switch in said trunk circuit controllable from the dial of a connected control operators position for directing the connection of one of said other operators positions to said trunk circuit, means operative following said transfer for disconnecting said trunk circuit from said control operators position, and a dial at each of said other positions for controlling said marker switch to direct the transfer of the connection of said trunk circuit from one of said other positions to another of said other positions.

13. In a telephone system, an incoming trunk circuit, a plurality of control operators positions each having an impulse generating means, means for connecting said trunk circuit with an idle one of said positions, a plurality of other operators positions having access to said trunk circuit, and marking means in said trunk circuit controllable from the impulse generating means of a connected control operators position for marking a desired group of said other operators positions and for directing the connection of one of said marked operators positions to said trunk circuit.

CHARLES DE VRIENDT. HENRI E. A. BORZER. 

